Providing goods and/or services to a group of people at a particular time and place presents numerous logistical problems. A particular problem that arises is that some customers demand prompt service or otherwise a sales opportunity may be lost. A large number of businesses and other agencies provide goods and services that are valuable to consumers only when they can be provided at a proper time and place. Moreover, these goods and services may call for some advance planning immediately prior to providing the goods or services to such customers. This may be a particular problem when dealing with crowds, e.g., when large numbers of potential customers demand prompt service at a given time, and if no such service is provided, then opportunities to be a service provider may be lost.